xref: /llvm-project/flang/lib/Parser/expr-parsers.cpp (revision 68f4e46c432ea2f1f8d33c6dc9345f6e2afeec4a) 
1 //===-- lib/Parser/expr-parsers.cpp ---------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // Per-type parsers for expressions.
10 
11 #include "expr-parsers.h"
12 #include "basic-parsers.h"
13 #include "misc-parsers.h"
14 #include "stmt-parser.h"
15 #include "token-parsers.h"
16 #include "type-parser-implementation.h"
17 #include "flang/Parser/characters.h"
18 #include "flang/Parser/parse-tree.h"
19 
20 namespace Fortran::parser {
21 
22 // R764 boz-literal-constant -> binary-constant | octal-constant | hex-constant
23 // R765 binary-constant -> B ' digit [digit]... ' | B " digit [digit]... "
24 // R766 octal-constant -> O ' digit [digit]... ' | O " digit [digit]... "
25 // R767 hex-constant ->
26 //        Z ' hex-digit [hex-digit]... ' | Z " hex-digit [hex-digit]... "
27 // extension: X accepted for Z
28 // extension: BOZX suffix accepted
29 TYPE_PARSER(construct<BOZLiteralConstant>(BOZLiteral{}))
30 
31 // R769 array-constructor -> (/ ac-spec /) | lbracket ac-spec rbracket
32 TYPE_CONTEXT_PARSER("array constructor"_en_US,
33     construct<ArrayConstructor>(
34         "(/" >> Parser<AcSpec>{} / "/)" || bracketed(Parser<AcSpec>{})))
35 
36 // R770 ac-spec -> type-spec :: | [type-spec ::] ac-value-list
37 TYPE_PARSER(construct<AcSpec>(maybe(typeSpec / "::"),
38                 nonemptyList("expected array constructor values"_err_en_US,
39                     Parser<AcValue>{})) ||
40     construct<AcSpec>(typeSpec / "::"))
41 
42 // R773 ac-value -> expr | ac-implied-do
43 TYPE_PARSER(
44     // PGI/Intel extension: accept triplets in array constructors
45     extension<LanguageFeature::TripletInArrayConstructor>(
46         "nonstandard usage: triplet in array constructor"_port_en_US,
47         construct<AcValue>(construct<AcValue::Triplet>(scalarIntExpr,
48             ":" >> scalarIntExpr, maybe(":" >> scalarIntExpr)))) ||
49     construct<AcValue>(indirect(expr)) ||
50     construct<AcValue>(indirect(Parser<AcImpliedDo>{})))
51 
52 // R774 ac-implied-do -> ( ac-value-list , ac-implied-do-control )
53 TYPE_PARSER(parenthesized(
54     construct<AcImpliedDo>(nonemptyList(Parser<AcValue>{} / lookAhead(","_tok)),
55         "," >> Parser<AcImpliedDoControl>{})))
56 
57 // R775 ac-implied-do-control ->
58 //        [integer-type-spec ::] ac-do-variable = scalar-int-expr ,
59 //        scalar-int-expr [, scalar-int-expr]
60 // R776 ac-do-variable -> do-variable
61 TYPE_PARSER(construct<AcImpliedDoControl>(
62     maybe(integerTypeSpec / "::"), loopBounds(scalarIntExpr)))
63 
64 // R1001 primary ->
65 //         literal-constant | designator | array-constructor |
66 //         structure-constructor | function-reference | type-param-inquiry |
67 //         type-param-name | ( expr )
68 // type-param-inquiry is parsed as a structure component, except for
69 // substring%KIND/LEN
70 constexpr auto primary{instrumented("primary"_en_US,
71     first(construct<Expr>(indirect(Parser<CharLiteralConstantSubstring>{})),
72         construct<Expr>(literalConstant),
73         construct<Expr>(construct<Expr::Parentheses>(parenthesized(expr))),
74         construct<Expr>(indirect(functionReference) / !"("_tok / !"%"_tok),
75         construct<Expr>(designator / !"("_tok / !"%"_tok),
76         construct<Expr>(indirect(Parser<SubstringInquiry>{})), // %LEN or %KIND
77         construct<Expr>(Parser<StructureConstructor>{}),
78         construct<Expr>(Parser<ArrayConstructor>{}),
79         // PGI/XLF extension: COMPLEX constructor (x,y)
80         construct<Expr>(parenthesized(
81             construct<Expr::ComplexConstructor>(expr, "," >> expr))),
82         extension<LanguageFeature::PercentLOC>(
83             "nonstandard usage: %LOC"_port_en_US,
84             construct<Expr>("%LOC" >> parenthesized(construct<Expr::PercentLoc>(
85                                           indirect(variable)))))))};
86 
87 // R1002 level-1-expr -> [defined-unary-op] primary
88 // TODO: Reasonable extension: permit multiple defined-unary-ops
89 constexpr auto level1Expr{sourced(
90     primary || // must come before define op to resolve .TRUE._8 ambiguity
91     construct<Expr>(construct<Expr::DefinedUnary>(definedOpName, primary)))};
92 
93 // R1004 mult-operand -> level-1-expr [power-op mult-operand]
94 // R1007 power-op -> **
95 // Exponentiation (**) is Fortran's only right-associative binary operation.
96 struct MultOperand {
97   using resultType = Expr;
98   constexpr MultOperand() {}
99   static inline std::optional<Expr> Parse(ParseState &);
100 };
101 
102 // Extension: allow + or - before a mult-operand
103 // Such a unary operand has lower precedence than exponentiation,
104 // so -x**2 is -(x**2), not (-x)**2; this matches all other
105 // compilers with this extension.
106 static constexpr auto standardMultOperand{sourced(MultOperand{})};
107 static constexpr auto multOperand{standardMultOperand ||
108     extension<LanguageFeature::SignedMultOperand>(
109         "nonstandard usage: signed mult-operand"_port_en_US,
110         construct<Expr>(
111             construct<Expr::UnaryPlus>("+" >> standardMultOperand))) ||
112     extension<LanguageFeature::SignedMultOperand>(
113         "nonstandard usage: signed mult-operand"_port_en_US,
114         construct<Expr>(construct<Expr::Negate>("-" >> standardMultOperand)))};
115 
116 inline std::optional<Expr> MultOperand::Parse(ParseState &state) {
117   std::optional<Expr> result{level1Expr.Parse(state)};
118   if (result) {
119     static constexpr auto op{attempt("**"_tok)};
120     if (op.Parse(state)) {
121       std::function<Expr(Expr &&)> power{[&result](Expr &&right) {
122         return Expr{Expr::Power(std::move(result).value(), std::move(right))};
123       }};
124       return applyLambda(power, multOperand).Parse(state); // right-recursive
125     }
126   }
127   return result;
128 }
129 
130 // R1005 add-operand -> [add-operand mult-op] mult-operand
131 // R1008 mult-op -> * | /
132 // The left recursion in the grammar is implemented iteratively.
133 struct AddOperand {
134   using resultType = Expr;
135   constexpr AddOperand() {}
136   static inline std::optional<Expr> Parse(ParseState &state) {
137     std::optional<Expr> result{multOperand.Parse(state)};
138     if (result) {
139       auto source{result->source};
140       std::function<Expr(Expr &&)> multiply{[&result](Expr &&right) {
141         return Expr{
142             Expr::Multiply(std::move(result).value(), std::move(right))};
143       }};
144       std::function<Expr(Expr &&)> divide{[&result](Expr &&right) {
145         return Expr{Expr::Divide(std::move(result).value(), std::move(right))};
146       }};
147       auto more{attempt(sourced("*" >> applyLambda(multiply, multOperand) ||
148           "/" >> applyLambda(divide, multOperand)))};
149       while (std::optional<Expr> next{more.Parse(state)}) {
150         result = std::move(next);
151         result->source.ExtendToCover(source);
152       }
153     }
154     return result;
155   }
156 };
157 constexpr AddOperand addOperand;
158 
159 // R1006 level-2-expr -> [[level-2-expr] add-op] add-operand
160 // R1009 add-op -> + | -
161 // These are left-recursive productions, implemented iteratively.
162 // Note that standard Fortran admits a unary + or - to appear only here,
163 // by means of a missing first operand; e.g., 2*-3 is valid in C but not
164 // standard Fortran.  We accept unary + and - to appear before any primary
165 // as an extension.
166 struct Level2Expr {
167   using resultType = Expr;
168   constexpr Level2Expr() {}
169   static inline std::optional<Expr> Parse(ParseState &state) {
170     static constexpr auto unary{
171         sourced(
172             construct<Expr>(construct<Expr::UnaryPlus>("+" >> addOperand)) ||
173             construct<Expr>(construct<Expr::Negate>("-" >> addOperand))) ||
174         addOperand};
175     std::optional<Expr> result{unary.Parse(state)};
176     if (result) {
177       auto source{result->source};
178       std::function<Expr(Expr &&)> add{[&result](Expr &&right) {
179         return Expr{Expr::Add(std::move(result).value(), std::move(right))};
180       }};
181       std::function<Expr(Expr &&)> subtract{[&result](Expr &&right) {
182         return Expr{
183             Expr::Subtract(std::move(result).value(), std::move(right))};
184       }};
185       auto more{attempt(sourced("+" >> applyLambda(add, addOperand) ||
186           "-" >> applyLambda(subtract, addOperand)))};
187       while (std::optional<Expr> next{more.Parse(state)}) {
188         result = std::move(next);
189         result->source.ExtendToCover(source);
190       }
191     }
192     return result;
193   }
194 };
195 constexpr Level2Expr level2Expr;
196 
197 // R1010 level-3-expr -> [level-3-expr concat-op] level-2-expr
198 // R1011 concat-op -> //
199 // Concatenation (//) is left-associative for parsing performance, although
200 // one would never notice if it were right-associated.
201 struct Level3Expr {
202   using resultType = Expr;
203   constexpr Level3Expr() {}
204   static inline std::optional<Expr> Parse(ParseState &state) {
205     std::optional<Expr> result{level2Expr.Parse(state)};
206     if (result) {
207       auto source{result->source};
208       std::function<Expr(Expr &&)> concat{[&result](Expr &&right) {
209         return Expr{Expr::Concat(std::move(result).value(), std::move(right))};
210       }};
211       auto more{attempt(sourced("//" >> applyLambda(concat, level2Expr)))};
212       while (std::optional<Expr> next{more.Parse(state)}) {
213         result = std::move(next);
214         result->source.ExtendToCover(source);
215       }
216     }
217     return result;
218   }
219 };
220 constexpr Level3Expr level3Expr;
221 
222 // R1012 level-4-expr -> [level-3-expr rel-op] level-3-expr
223 // R1013 rel-op ->
224 //         .EQ. | .NE. | .LT. | .LE. | .GT. | .GE. |
225 //          == | /= | < | <= | > | >=  @ | <>
226 // N.B. relations are not recursive (i.e., LOGICAL is not ordered)
227 struct Level4Expr {
228   using resultType = Expr;
229   constexpr Level4Expr() {}
230   static inline std::optional<Expr> Parse(ParseState &state) {
231     std::optional<Expr> result{level3Expr.Parse(state)};
232     if (result) {
233       auto source{result->source};
234       std::function<Expr(Expr &&)> lt{[&result](Expr &&right) {
235         return Expr{Expr::LT(std::move(result).value(), std::move(right))};
236       }};
237       std::function<Expr(Expr &&)> le{[&result](Expr &&right) {
238         return Expr{Expr::LE(std::move(result).value(), std::move(right))};
239       }};
240       std::function<Expr(Expr &&)> eq{[&result](Expr &&right) {
241         return Expr{Expr::EQ(std::move(result).value(), std::move(right))};
242       }};
243       std::function<Expr(Expr &&)> ne{[&result](Expr &&right) {
244         return Expr{Expr::NE(std::move(result).value(), std::move(right))};
245       }};
246       std::function<Expr(Expr &&)> ge{[&result](Expr &&right) {
247         return Expr{Expr::GE(std::move(result).value(), std::move(right))};
248       }};
249       std::function<Expr(Expr &&)> gt{[&result](Expr &&right) {
250         return Expr{Expr::GT(std::move(result).value(), std::move(right))};
251       }};
252       auto more{attempt(
253           sourced((".LT."_tok || "<"_tok) >> applyLambda(lt, level3Expr) ||
254               (".LE."_tok || "<="_tok) >> applyLambda(le, level3Expr) ||
255               (".EQ."_tok || "=="_tok) >> applyLambda(eq, level3Expr) ||
256               (".NE."_tok || "/="_tok ||
257                   extension<LanguageFeature::AlternativeNE>(
258                       "nonstandard usage: <> for /= or .NE."_port_en_US,
259                       "<>"_tok /* PGI/Cray extension; Cray also has .LG. */)) >>
260                   applyLambda(ne, level3Expr) ||
261               (".GE."_tok || ">="_tok) >> applyLambda(ge, level3Expr) ||
262               (".GT."_tok || ">"_tok) >> applyLambda(gt, level3Expr)))};
263       if (std::optional<Expr> next{more.Parse(state)}) {
264         next->source.ExtendToCover(source);
265         return next;
266       }
267     }
268     return result;
269   }
270 };
271 constexpr Level4Expr level4Expr;
272 
273 // R1014 and-operand -> [not-op] level-4-expr
274 // R1018 not-op -> .NOT.
275 // N.B. Fortran's .NOT. binds less tightly than its comparison operators do.
276 // PGI/Intel extension: accept multiple .NOT. operators
277 struct AndOperand {
278   using resultType = Expr;
279   constexpr AndOperand() {}
280   static inline std::optional<Expr> Parse(ParseState &);
281 };
282 constexpr AndOperand andOperand;
283 
284 // Match a logical operator or, optionally, its abbreviation.
285 inline constexpr auto logicalOp(const char *op, const char *abbrev) {
286   return TokenStringMatch{op} ||
287       extension<LanguageFeature::LogicalAbbreviations>(
288           "nonstandard usage: abbreviated LOGICAL operator"_port_en_US,
289           TokenStringMatch{abbrev});
290 }
291 
292 inline std::optional<Expr> AndOperand::Parse(ParseState &state) {
293   static constexpr auto notOp{attempt(logicalOp(".NOT.", ".N.") >> andOperand)};
294   if (std::optional<Expr> negation{notOp.Parse(state)}) {
295     return Expr{Expr::NOT{std::move(*negation)}};
296   } else {
297     return level4Expr.Parse(state);
298   }
299 }
300 
301 // R1015 or-operand -> [or-operand and-op] and-operand
302 // R1019 and-op -> .AND.
303 // .AND. is left-associative
304 struct OrOperand {
305   using resultType = Expr;
306   constexpr OrOperand() {}
307   static inline std::optional<Expr> Parse(ParseState &state) {
308     static constexpr auto operand{sourced(andOperand)};
309     std::optional<Expr> result{operand.Parse(state)};
310     if (result) {
311       auto source{result->source};
312       std::function<Expr(Expr &&)> logicalAnd{[&result](Expr &&right) {
313         return Expr{Expr::AND(std::move(result).value(), std::move(right))};
314       }};
315       auto more{attempt(sourced(
316           logicalOp(".AND.", ".A.") >> applyLambda(logicalAnd, andOperand)))};
317       while (std::optional<Expr> next{more.Parse(state)}) {
318         result = std::move(next);
319         result->source.ExtendToCover(source);
320       }
321     }
322     return result;
323   }
324 };
325 constexpr OrOperand orOperand;
326 
327 // R1016 equiv-operand -> [equiv-operand or-op] or-operand
328 // R1020 or-op -> .OR.
329 // .OR. is left-associative
330 struct EquivOperand {
331   using resultType = Expr;
332   constexpr EquivOperand() {}
333   static inline std::optional<Expr> Parse(ParseState &state) {
334     std::optional<Expr> result{orOperand.Parse(state)};
335     if (result) {
336       auto source{result->source};
337       std::function<Expr(Expr &&)> logicalOr{[&result](Expr &&right) {
338         return Expr{Expr::OR(std::move(result).value(), std::move(right))};
339       }};
340       auto more{attempt(sourced(
341           logicalOp(".OR.", ".O.") >> applyLambda(logicalOr, orOperand)))};
342       while (std::optional<Expr> next{more.Parse(state)}) {
343         result = std::move(next);
344         result->source.ExtendToCover(source);
345       }
346     }
347     return result;
348   }
349 };
350 constexpr EquivOperand equivOperand;
351 
352 // R1017 level-5-expr -> [level-5-expr equiv-op] equiv-operand
353 // R1021 equiv-op -> .EQV. | .NEQV.
354 // Logical equivalence is left-associative.
355 // Extension: .XOR. as synonym for .NEQV.
356 struct Level5Expr {
357   using resultType = Expr;
358   constexpr Level5Expr() {}
359   static inline std::optional<Expr> Parse(ParseState &state) {
360     std::optional<Expr> result{equivOperand.Parse(state)};
361     if (result) {
362       auto source{result->source};
363       std::function<Expr(Expr &&)> eqv{[&result](Expr &&right) {
364         return Expr{Expr::EQV(std::move(result).value(), std::move(right))};
365       }};
366       std::function<Expr(Expr &&)> neqv{[&result](Expr &&right) {
367         return Expr{Expr::NEQV(std::move(result).value(), std::move(right))};
368       }};
369       auto more{attempt(sourced(".EQV." >> applyLambda(eqv, equivOperand) ||
370           (".NEQV."_tok ||
371               extension<LanguageFeature::XOROperator>(
372                   "nonstandard usage: .XOR./.X. spelling of .NEQV."_port_en_US,
373                   logicalOp(".XOR.", ".X."))) >>
374               applyLambda(neqv, equivOperand)))};
375       while (std::optional<Expr> next{more.Parse(state)}) {
376         result = std::move(next);
377         result->source.ExtendToCover(source);
378       }
379     }
380     return result;
381   }
382 };
383 constexpr Level5Expr level5Expr;
384 
385 // R1022 expr -> [expr defined-binary-op] level-5-expr
386 // Defined binary operators associate leftwards.
387 template <> std::optional<Expr> Parser<Expr>::Parse(ParseState &state) {
388   std::optional<Expr> result{level5Expr.Parse(state)};
389   if (result) {
390     auto source{result->source};
391     std::function<Expr(DefinedOpName &&, Expr &&)> defBinOp{
392         [&result](DefinedOpName &&op, Expr &&right) {
393           return Expr{Expr::DefinedBinary(
394               std::move(op), std::move(result).value(), std::move(right))};
395         }};
396     auto more{attempt(
397         sourced(applyLambda<Expr>(defBinOp, definedOpName, level5Expr)))};
398     while (std::optional<Expr> next{more.Parse(state)}) {
399       result = std::move(next);
400       result->source.ExtendToCover(source);
401     }
402   }
403   return result;
404 }
405 
406 // R1003 defined-unary-op -> . letter [letter]... .
407 // R1023 defined-binary-op -> . letter [letter]... .
408 // R1414 local-defined-operator -> defined-unary-op | defined-binary-op
409 // R1415 use-defined-operator -> defined-unary-op | defined-binary-op
410 // C1003 A defined operator must be distinct from logical literal constants
411 // and intrinsic operator names; this is handled by attempting their parses
412 // first, and by name resolution on their definitions, for best errors.
413 // N.B. The name of the operator is captured with the dots around it.
414 constexpr auto definedOpNameChar{letter ||
415     extension<LanguageFeature::PunctuationInNames>(
416         "nonstandard usage: non-alphabetic character in defined operator"_port_en_US,
417         "$@"_ch)};
418 TYPE_PARSER(
419     space >> construct<DefinedOpName>(sourced("."_ch >>
420                  some(definedOpNameChar) >> construct<Name>() / "."_ch)))
421 
422 // R1028 specification-expr -> scalar-int-expr
423 TYPE_PARSER(construct<SpecificationExpr>(scalarIntExpr))
424 
425 // R1032 assignment-stmt -> variable = expr
426 TYPE_CONTEXT_PARSER("assignment statement"_en_US,
427     construct<AssignmentStmt>(variable / "=", expr))
428 
429 // R1033 pointer-assignment-stmt ->
430 //         data-pointer-object [( bounds-spec-list )] => data-target |
431 //         data-pointer-object ( bounds-remapping-list ) => data-target |
432 //         proc-pointer-object => proc-target
433 // R1034 data-pointer-object ->
434 //         variable-name | scalar-variable % data-pointer-component-name
435 //   C1022 a scalar-variable shall be a data-ref
436 //   C1024 a data-pointer-object shall not be a coindexed object
437 // R1038 proc-pointer-object -> proc-pointer-name | proc-component-ref
438 //
439 // A distinction can't be made at the time of the initial parse between
440 // data-pointer-object and proc-pointer-object, or between data-target
441 // and proc-target.
442 TYPE_CONTEXT_PARSER("pointer assignment statement"_en_US,
443     construct<PointerAssignmentStmt>(dataRef,
444         parenthesized(nonemptyList(Parser<BoundsRemapping>{})), "=>" >> expr) ||
445         construct<PointerAssignmentStmt>(dataRef,
446             defaulted(parenthesized(nonemptyList(Parser<BoundsSpec>{}))),
447             "=>" >> expr))
448 
449 // R1035 bounds-spec -> lower-bound-expr :
450 TYPE_PARSER(construct<BoundsSpec>(boundExpr / ":"))
451 
452 // R1036 bounds-remapping -> lower-bound-expr : upper-bound-expr
453 TYPE_PARSER(construct<BoundsRemapping>(boundExpr / ":", boundExpr))
454 
455 // R1039 proc-component-ref -> scalar-variable % procedure-component-name
456 //   C1027 the scalar-variable must be a data-ref without coindices.
457 TYPE_PARSER(construct<ProcComponentRef>(structureComponent))
458 
459 // R1041 where-stmt -> WHERE ( mask-expr ) where-assignment-stmt
460 // R1045 where-assignment-stmt -> assignment-stmt
461 // R1046 mask-expr -> logical-expr
462 TYPE_CONTEXT_PARSER("WHERE statement"_en_US,
463     construct<WhereStmt>("WHERE" >> parenthesized(logicalExpr), assignmentStmt))
464 
465 // R1042 where-construct ->
466 //         where-construct-stmt [where-body-construct]...
467 //         [masked-elsewhere-stmt [where-body-construct]...]...
468 //         [elsewhere-stmt [where-body-construct]...] end-where-stmt
469 TYPE_CONTEXT_PARSER("WHERE construct"_en_US,
470     construct<WhereConstruct>(statement(Parser<WhereConstructStmt>{}),
471         many(whereBodyConstruct),
472         many(construct<WhereConstruct::MaskedElsewhere>(
473             statement(Parser<MaskedElsewhereStmt>{}),
474             many(whereBodyConstruct))),
475         maybe(construct<WhereConstruct::Elsewhere>(
476             statement(Parser<ElsewhereStmt>{}), many(whereBodyConstruct))),
477         statement(Parser<EndWhereStmt>{})))
478 
479 // R1043 where-construct-stmt -> [where-construct-name :] WHERE ( mask-expr )
480 TYPE_CONTEXT_PARSER("WHERE construct statement"_en_US,
481     construct<WhereConstructStmt>(
482         maybe(name / ":"), "WHERE" >> parenthesized(logicalExpr)))
483 
484 // R1044 where-body-construct ->
485 //         where-assignment-stmt | where-stmt | where-construct
486 TYPE_PARSER(construct<WhereBodyConstruct>(statement(assignmentStmt)) ||
487     construct<WhereBodyConstruct>(statement(whereStmt)) ||
488     construct<WhereBodyConstruct>(indirect(whereConstruct)))
489 
490 // R1047 masked-elsewhere-stmt ->
491 //         ELSEWHERE ( mask-expr ) [where-construct-name]
492 TYPE_CONTEXT_PARSER("masked ELSEWHERE statement"_en_US,
493     construct<MaskedElsewhereStmt>(
494         "ELSE WHERE" >> parenthesized(logicalExpr), maybe(name)))
495 
496 // R1048 elsewhere-stmt -> ELSEWHERE [where-construct-name]
497 TYPE_CONTEXT_PARSER("ELSEWHERE statement"_en_US,
498     construct<ElsewhereStmt>("ELSE WHERE" >> maybe(name)))
499 
500 // R1049 end-where-stmt -> ENDWHERE [where-construct-name]
501 TYPE_CONTEXT_PARSER("END WHERE statement"_en_US,
502     construct<EndWhereStmt>(recovery(
503         "END WHERE" >> maybe(name), namedConstructEndStmtErrorRecovery)))
504 
505 // R1050 forall-construct ->
506 //         forall-construct-stmt [forall-body-construct]... end-forall-stmt
507 TYPE_CONTEXT_PARSER("FORALL construct"_en_US,
508     construct<ForallConstruct>(statement(Parser<ForallConstructStmt>{}),
509         many(Parser<ForallBodyConstruct>{}),
510         statement(Parser<EndForallStmt>{})))
511 
512 // R1051 forall-construct-stmt ->
513 //         [forall-construct-name :] FORALL concurrent-header
514 TYPE_CONTEXT_PARSER("FORALL construct statement"_en_US,
515     construct<ForallConstructStmt>(
516         maybe(name / ":"), "FORALL" >> indirect(concurrentHeader)))
517 
518 // R1052 forall-body-construct ->
519 //         forall-assignment-stmt | where-stmt | where-construct |
520 //         forall-construct | forall-stmt
521 TYPE_PARSER(construct<ForallBodyConstruct>(statement(forallAssignmentStmt)) ||
522     construct<ForallBodyConstruct>(statement(whereStmt)) ||
523     construct<ForallBodyConstruct>(whereConstruct) ||
524     construct<ForallBodyConstruct>(indirect(forallConstruct)) ||
525     construct<ForallBodyConstruct>(statement(forallStmt)))
526 
527 // R1053 forall-assignment-stmt -> assignment-stmt | pointer-assignment-stmt
528 TYPE_PARSER(construct<ForallAssignmentStmt>(assignmentStmt) ||
529     construct<ForallAssignmentStmt>(pointerAssignmentStmt))
530 
531 // R1054 end-forall-stmt -> END FORALL [forall-construct-name]
532 TYPE_CONTEXT_PARSER("END FORALL statement"_en_US,
533     construct<EndForallStmt>(recovery(
534         "END FORALL" >> maybe(name), namedConstructEndStmtErrorRecovery)))
535 
536 // R1055 forall-stmt -> FORALL concurrent-header forall-assignment-stmt
537 TYPE_CONTEXT_PARSER("FORALL statement"_en_US,
538     construct<ForallStmt>("FORALL" >> indirect(concurrentHeader),
539         unlabeledStatement(forallAssignmentStmt)))
540 } // namespace Fortran::parser
541